Contributing: Getting Started - Global-Conflicts-ArmA/Olsen-Framework-Arma-3 GitHub Wiki
Scripting Standards
Please refer to ACE 3 Coding Guidelines
Code Editor
I highly recommend using a code editor like Notepad++ or Visual Studio. It will help you spot errors in your code by using syntax highlighting. You can download a plugin for Notepad++ that is specifically made for ArmA 3 code here.
As an alternative you can also use Atom, it also has a plugin for SQF syntax highlighting with snippets and a linter.